Africa accounts for about nine in ten deaths and cases, with more than a third concentrated in two countries - Nigeria and the Democratic Republic of Congo - where conflict has forced millions to flee their homes, WHO data shows.

Tackling malaria in such places requires new strategies since those used elsewhere - such as distributing bed nets - do not work, said Richard Allen, head of The Mentor Initiative, an organisation focused on disease control in humanitarian crises.

"All too often we try to make the wrong tool fit the context," Allen said in an interview ahead of the Multilateral Initiative on Malaria's (MIM) pan-African conference this week.

"Where is a displaced person going to hang a net?" he told the Thomson Reuters Foundation.

Researchers presented possible solutions at the conference in Senegal's capital Dakar, such as insecticide-treated plastic sheeting that can be used for shelters, and giving health workers mini malaria kits in a backpack.

WHO's global malaria programme director, Pedro Alonso, said the right tools were being used but noted that malaria surged in conflict zones for other reasons.

"Whenever there is an emergency, if the country is endemic for malaria (then) disruption of health services, movement of people and malnutrition ... all lead to malaria," he told the Thomson Reuters Foundation.

Malaria killed twice as many people as Ebola during West Africa's Ebola crisis, and is responsible for the majority of deaths in war-torn South Sudan and in parts of Nigeria battling Boko Haram, Alonso said.

Global funding for the disease has levelled off while populations have grown, meaning the amount of money per capita to fight malaria in at-risk countries has dropped, he added.